Clinical Thyroid Disease Flashcards

1
Q

4 categories of thyroid disease

A

Hyperthyroidism
Hypothyroidism
Goitre
Thyroid cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

3 parts of the thyroid gland

A

Right lobe
Left lobe
Isthmus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Hormone levels in primary hypothyroidism

A
Raised TSH (due to the body thinking you are hypothyroid)
Low FT4 and FT3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Hormone levels in subclinical (compensated) hypothyroidism

A

Raised TSH

Normal FT4 and FT3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is subclinical hypothyroidism?

A

The pituitary has been into overdrive and so the normal values have been maintained

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Hormone levels in secondary hypothyroidism (pituitary)

A

Low TSH

Low FT4 and FT3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Investigations of hypothyroidism

A
TFTs - TSH/FT4
Autoantibodies; TPO (thyroid peroxidase antibodies)
FBC (MCV increased)
Lipids (hypercholesteraemia)
Hyponatraemia 
Increased muscle enzymes, ALT, CK
Hyperprolactinaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Presentation of hypothyroidism

A
Weight gain 
Lethargy 
Feeling Cold
Constipation 
Heavy periods
Dry skin/hair
Bradycardia
Slow reflexes 
Goitre 
Puffy face
Large tongue 
Hoarse voice 
Coma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Presentation of hyperthyroidism

A
Weight loss
Anxiety/irritability
Heat intolerance
Bowel frequency 
Light periods
Sweaty palms
Palpitations
Hyperreflexia/tremors
Goitre
Thyroid eye symptoms/signs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Normal range of TSH

A

0.3-3.3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Normal range of FT4

A

10-25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What TFTs to look at first….

A

FT4 will tell you if patient has subclinical or overt disease
Then look at TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens in respect to autoimmunity in hypothyroidism?

A

The antibodies destroy the gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens in respect to autoimmunity in hyperthyroidism?

A

The antibodies stimulate the gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Causes of primary hypothyroidism

A
Congenital 
- developmental 
- dyshormogenesis
Autoimmune thyroid disease - Hashimotos 
Post-op/post-radioactive iodine
External RT for head and neck cancers
Drugs 
- Antithyroid drugs 
- Amoidarones
- Lithium 
- Interferon
- Immune checkpoint inhibitors 
Chronic Iodine deficiency 
Post-subacute thyroiditis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the commonest reason for hypothyroidism in the UK?

A

Hashimotos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the commonest reason for hypothyroidism worldwide?

A

Chronic iodine deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Causes of secondary/tertiary hypothyroidism

A
Pituitary tumour
Craniopharyngioma
Post pituitary surgery or radiotherapy 
Sheehans syndrome 
Isolated TRH deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Your chance of thyroid progression is higher if you have a raised what?

A

TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the causes of primary thyrotoxicosis?

A

Graves disease (70%)
Toxic multinodular goitre (20%)
Toxic adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is thyrotoxicosis?

A

A condition due to excess thyroid hormones - therefore including hyperthyroidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the cause of secondary thyrotoxicosis and how common is this?

A

Pituitary adenoma secreting TSH

quite rare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Causes of thyrotoxicosis without hyperthyroidism

A

Destructive thyroiditis

Excessive thyroxine administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What can cause destructive thyroiditis?

A

Post partum
Subacute (De Quervains)
Amoidarone induced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What % of hyperthyroidism does graves disease make up?

A

70-80%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which gender gets graves disease more?

A

F > M

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Pathology of graves disease

A

Stimulating antibodies (thyroid peroxidase antibodies and TSH receptor antibodies)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the most common cause of thyrotoxicosis in the elderly?

A

Multinodular goitre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Will multinodular goitre go into spontaneous remission?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is subacute (de Quervians) thyroiditis?

A

Thyroiditis due to a viral trigger e.g. enteroviruses, cockasackie

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What age of patients get subacute/de quervians thyroiditis?

A

Generally younger patients < 50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Presentation of subacute/de quervians thyroiditis

A
Painful goitre
Fever 
Myalgia 
ESR increased
Thyrotoxicosis for a while(3-6 weeks) and then hypothyroid (3-6 months)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What may subacute/de quervians thyroidits require in the short term?

A

NSAIDs and steriods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Treatment of hyperthyroidism

A

RAI (radioiodine)
ATD (antithyroid drugs)
Surgery
Beta blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is implicated in the management of symptoms in hyperthyroidism?

A

Beta blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the anti thyroid drugs?

A

Carbimazole

Propulthiourcacil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Two ways to give ATD

A
  1. Titration regime - start at highest dose then reduce dose when symptoms get better over time
  2. Block replace - start at high dose and then when symptoms improve, instead of cutting down, you add thyroxine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What does RAI do?

A

High dose which is ablative, destroying the gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Cautions to take when have had radioiodine

A

Cant have contact with young children under 18 for 4 weeks
No contact with pregnant women
Can set off airport alarms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

S/Es of RAI

A

70% hypothyroid

Eye problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Concerns in subclinical hyperthyroidism

A

Decreased bone density in post menopausal women

AF 3x increase in over 60s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Treatment of hypothyroidism

A

Levothyroxine (T4) tablets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Doses of levothyroxine (T4) used in the treatment of hypothyroidism

A

Initial dose 50mcg/day

After 2 weeks increase to 100mcg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How to take levothyroxine?

A

Same time every day
Empty stomach
Not interfering with other medications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How long do the levels take to go back to normal after taking replacement of thyroxine?

A

6-8 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What situations would you need to adjust the dose of levothyroxine and to what and why?

A

Ischaemic heart disease - start at lower dose and increase slowly as risk of precipitating angina
Pregnancy - need increased LT4 dose as increased thyroxine requirement
Postpartum thyroiditis - trial withdrawal
Myxedema coma - very rare emergency a coma from hypothyroidism - need IV T3 (steroid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What would be present for you to consider for treatment in Subclinical hypothyroidism?

A

TSH > 10
TSH >5 if positive thyroid antibodies
TSH elevated with symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Complications of treatment of subclinical hypothyroidism

A

Osteopenia and AF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

How long do you trial for treatment for subclinical hypothyroidism and is this continued?

A

3 to 4 months

Continue if symptomatic improvement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is there a risk of when treating subclinical hypothyroidism?

A

Overtreatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

When in the pregnancy do you need to increase levothyroxine dose?

A

Pre-conceptually

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Types of thyroid cancer

A
Papillary 
Follicular
Anaplastic 
Lymphoma
Medullary
53
Q

Most common type of thyroid cancer

A

Papillary

54
Q

Features of papillary thyroid cancer

A

Multifocal, spread to lymph nodes

Good prognosis

55
Q

Features of follicular thyroid cancer

A

Usually single lesion
Spreads by bloodstream
Metastases to lung and bone
Good prognosis if resectable

56
Q

Treatment of thyroid cancer

A

Near total thyroidectomy and lymph node dissection

High dose radioiodine (ablative)

57
Q

Prognosis of thyroid cancer is poor if….

A
< 16 y/o 
> 45 y/o
Tumour size 
Spread outside tumour capsule
TNM staging
58
Q

What would need to be given after treatment with radioiodine?

A

Long term suppressive doses of thyroxine

59
Q

What is the follow up after treatment for thyroid cancer?

A

Thyroglobulin checked once a year once stable

Whole body iodine scanning (following 2-4 weeks of thyroxine withdrawal)

60
Q

Where does the tumour arise from in medullary thyroid cancer?

A

Parafollicular C cells

61
Q

What is medullary thyroid cancer often associated with?

A

MEN 2

62
Q

What is raised in medullary thyroid cancer?

A

Serum calcitonin levels

63
Q

Treatment of medullary thyroid cancer

A

Total thyroidectomy

64
Q

Why is there not a role for radioiodine in medullary thyroid cancer?

A

Because it is not a cancer of the thyroid cells

65
Q

Causes of goitre

A
Puberty
Pregnancy 
Grave's disease
Hashimoto's
Acute inflammation (De Quervians)
Chronic fibrotic inflammation (Reidels)
Iodine deficiency (endemic goitre)
Dyshormogenesis
Goitrogens
66
Q

Types of goitre

A
Multinodular
Diffuse
Cysts
Tumours
Miscellaneous
67
Q

In a solitary thyroid nodule, the risk of malignancy is higher in who?

A
Children
Adults < 30 y/o or > 60 y/o
Previous head and neck irradiation 
Pain
Cervical lymphadenopathy
68
Q

Investigations of a solitary thyroid nodule

A
TFTs
Isotope scanning if low TSH (hot nodule)
USS (benign vs malignant)
FNA 
CXT/TXR if large retrosternal extensions
69
Q

Hot nodule vs cold nodule

A

Hot - producing too much T3/T4

Cold - implies that area is not taking up enough

70
Q

Drug used to treat hyperthyroidism

A

Carbamezole

71
Q

Main side effect of carbamezole

A

Agranulocytosis

72
Q

What is agranulocytosis?

A

Knocks out neutrophils

73
Q

When treated with RAI, what will happen to the majority of people as a side effect?

A

Thyroid will go underactive (hypothyroid)

74
Q

What test is used to look at the thyroid?

A

USS

75
Q

What is often the pathology in primary hyperparathyroidism?

A

Only 1 gland over working

76
Q

Indications for surgery of primary hyperparathyroidism

A

Very high Ca
Kidney stones
Thin bones

77
Q

Penetrance of MEN 1 + 2

A

Very variable

78
Q

What do MEN 1 + 2 involve?

A

Tumours involving 2 or more endocrine glands

79
Q

Test for pheochromocytoma

A

Urinary catecholamines

80
Q

What type of tissue are C cells?

A

Neuroendocrine

81
Q

What cancer is a cancer of the C cells?

A

Medullary thyroid cancer

82
Q

Pathology of C cells cancer

A

Calcification

Leading to medullary carcinoma

83
Q

What is the problem with medullary thyroid cancer?

A

Tends to metastasise

84
Q

What is the C cell cancer precursor?

A

C cell hyperplasia

85
Q

Inheritance for MEN 1 + 2

A

Autosomal dominant

86
Q

What does the MIBG scan pick up?

A

Neuroendocrine tissue

87
Q

How common is MEN?

A

Really rare

88
Q

Treatment of MEN 2A

A

Alpha blockage to reduce effect of adrenaline e.g. phenoxytozamine

89
Q

What prophylactic treatment can be considered in MEN 2A?

A

Thyroidectomy

90
Q

What nerve runs through the thyroid?

A

Recurrent laryngeal nerve

91
Q

Autoantibodies (of the thyroid) are raised in what condition?

A

Both primary hypo and hyperthyroidism

92
Q

What thyroid test is not measured routinely?

A

T3

93
Q

Why must thyroxine treatment be started at a lower dose in older people?

A

Heart problems

94
Q

What can interfere with thyroxine?

A

Iron supplements

95
Q

Average dose of levothyroxine

A

125mg

96
Q

Too much levothyroxine can lead to……

A

Heart problems

Osteopenia / porosis

97
Q

Treatment of subclinical hypothyroidism

A

4.78 - 10 should be assessed but not automatically treated

98
Q

What predicts the risk of overt hypothyroidism?

A

Anti-TPO

99
Q

Eye signs of graves disease

A
Diplopia
Dry eyes
Exopthalmos 
Eye movement problems
Lid lag 
Lid retraction 
Proptosis 
Periorbital oedema
100
Q

What presentation of goitre is found in graves disease?

A

Smooth homogenous bilateral swelling

101
Q

Pathology of post partum thyroiditis

A

Destructive mediated thyroiditis - inflammation

102
Q

When does post partum thyroiditis occur?

A

8 weeks - 1 year post partum

103
Q

Can post partum thyroiditis come back in further pregnancies?

A

Yes

104
Q

What % of people with graves have TAB +ve?

A

70 - 80%

105
Q

Does thyroiditis always give clinical signs? Why?

A

No

Not overactive - it is not manufacturing more hormones, it is just putting more into the blood

106
Q

Treatment of thyroiditis

A

Manage symptoms e.g. beta blocker for tachycardia

107
Q

How would you tell the difference between graves and thyroiditis?

A

Iodine uptake scan

  • Graves would have an increased uptake as it is manufacturing new hormones
  • Thyroiditis would have not a big as an increased uptake as it is not manufacturing new hormones
108
Q

What is used for iodine in an iodine uptake scan?

A

Pertechestate

109
Q

Does Toxic multinodular goitre tend to go into spontaneous remission?

A

No

110
Q

How long is carbimazole taken for?

A

12 - 15 days

111
Q

What is the optimal therapy for MN goitre?

A

RAI

112
Q

When would RAI be used in graves?

A

Typically after relapse

113
Q

What is there a risk of when using ATDs? How common is this?

A

Agranulocytosis

1:250

114
Q

Thyroidectomies are only done when?

A

Intolerant of drug therapy

RAI not possible

115
Q

TSH receptor antibodies are present in 90-100% of what?

A

Graves disease

116
Q

Common clinical finding of graves disease

A

Pretibial myxoedema

Thyroid acropachy

117
Q

Who are anti-TPO antibodies found in?

A

Hashimotos

118
Q

What is thyroid acropachy?

A

Thickening of extremities

  • Digital clubbing
  • soft tissue swelling of hands and feet
  • periosteal new bone formation
119
Q

Effect of thyrotoxicosis on calcium levels

A

Hypercalcaemia

120
Q

What is the most important modifiable risk factor for the development of thyroid eye disease?

A

Smoking

121
Q

What is a thyroid storm?

A

Life threatening rare complication of thyrotoxicosis

122
Q

Who is a thyroid storm seen in?

A

Patients with established thyrotoxicosis

123
Q

What does NOT usually cause a thyroid storm?

A

Iatrogenic thyroxine

124
Q

Precipitating events of thyroid storm

A

Thyroid / non thyroid surgery
Trauma
Infection
Acute iodine load e.g. CT contrast media

125
Q

Presentation of thyroid storm

A
Fever > 38.5C
Tachycardia
Confusion and agitation 
Nausea and Vomiting
HF
HTN
Abnormal LFTs (may have jaundice)
126
Q

Treatment of thyroid storm

A
Symptomatic - paracetamol 
Treat underlying precipitating event 
BBs; typically IV propranolol 
ATDs; e.g. propylithiouracil 
Lugols iodine
Dexamethasone
127
Q

What does a tender goitre indicate?

A

DeQuervians/Subacute thyroiditis

128
Q

What is used to monitor the recurrence of medullary thyroid cancer?

A

Serum calcitonin levels